Project Summary/Abstract The proposal addresses NHLBI Topic of Special Interest HLS17-15, Development of mechanical circulatory support devices for individuals with congenital heart disease and single ventricle physiology after Fontan surgical palliation. The design was specifically stimulated by the requirements outlined to Perfusion Solutions, Inc. (PSI) by pediatric and congenital surgeon Dr. Pranava Sinha of the National Children?s Health System (CNHS) in Washington DC. The surgical treatment and management has dramatically advanced since the early days of development of surgical treatment of single ventricle heart disease. Patients now routinely survive into their teen and early adult years. However, significant morbidities develop, ranging from minimal exercise capability through terminal heart, liver and kidney pathologies. These are a product of diastolic heart dysfunction, and are not universally relieved with systemic assistance. There is a need for a long term cavopulmonary assist system which can bridge patients over the often very long wait for a donor heart or potentially serve as a destination therapy. A suitable device will provide flows and pressures for the superior and inferior vena cavae (defined as flows between 0.1 ? 3.0 lpm, pressure rises between 1 and 15 mmHg), blood compatibility in the venous circulation, and have minimal resistance to forward flow should pump rotation be interrupted. The PSI approach incorporates an axial flow impeller support by our proprietary ?MicroJ? hydrodynamic bearings. These bearings have minimal cross section to impede flow, and are completely open oven the non-work arc to enable maximum wash flow. The impeller is rotated and supported axially by a magnetic coupling to the impeller blade tips, to further minimize blockage or complexity in the flow path. During the phase I research, the impeller design will be optimized. A demonstrator pump, simplified outside the blood flow path to minimize unnecessary phase I cost, will be built and tested. Satisfaction of the success criteria will be shown, specifically, obtaining the defined hydraulic performance, minimal hemolysis, low static pressure drop, and an indication of long term durability. During Phase II, clinical prototypes will be built and evaluated in depth, including in vivo studies. PSI was incorporated in 2008 to commercialize the technology developed by Principal investigator Dr. William Smith during his career at the Cleveland Clinic; in 2012, after 30 Cleveland Clinic years, he retired and joined PSI full time. PSI has partnered for several years with Dr. Pranava Sinha at CNHSto use PSI?s PediPump as part of Dr. Sinha?s Fontan support research program. Dr. Sinha will continue as the medical design consultant for this new program, and lead the future in vivo program.